Convert Attached Garage to Family Room?

[Bill Ladd]

Hey folks, I'm looking for some advice regarding the ROI of converting a garage that's under the house (with basement access) to living space.

The house is a high-end single fam and it already has 1 detached garage and two off-street parking spaces. The extra garage wasn't used by the previous owners and is kind of awkward to access as it's behind the house and down under the main floor.

If I leave it as a garage, I'll have to install a drain so the driveway stops funneling water under the basement. I'll also have to replace the doors and install an opener.

The house isn't that big and it's customary in my area to convert the basement to a playroom. I can do that with or without the garage conversion, but I could add something extra if I made that living space (maybe a game/media room).

Thoughts?

What's worth more: A house with two garages or a house with one garage and a basement game/media room? If it's the game/media room, is the difference enough to justify finishing an additional 200sf of living space?